JP6814874B2 - How to honing gears with crosscuts - Google Patents

Description

The present invention is a method for applying a surface structure to a gear by gear honing .

Gears are heavily loaded by very high pressures and frictional forces, for example during operation in transmissions. Gears are often surrounded by a film of lubricant, such as oil, during operation to reduce the load on each gear and to minimize noise emissions from the gear due to uniform excitation that results in tooth vibration. ..

German Patent Application Publication No. 4231021

During the manufacture of gears, the teeth are often hard-finished by gear honing or gear grinding. Therefore, the surface structure formed on the gear teeth is not optimal for a film of lubricant applied to the gear to ensure that it protects the gear from frictional energy or noise damage and keeps the gear from moving. Absent. Therefore, due to the non-optimal lubricant film, the gears wear faster and generate more noise.

Patent Document 1 discloses a method and an apparatus for thread rolling involute tooth surface machining, in which a cross-cut structure is formed on the machined body by the pendulum motion of the variable transition body. A spherical tool is used here.

Against this background, the present method is a method of forming a surface structure on a gear in honing, in which at least one honing tool moves along the gear in a first direction using a first axial crossing angle. Then, at least one honing tool is moved along the gear in a second direction opposite to the first direction using the second axis crossing angle, and at least one honing tool is on the surface of the gear. The first streak made when moved in the first direction above is the second streak made when at least one honing tool is moved in the second direction on the surface of the gear. The first axis intersection angle and the second axis intersection angle are selected so that they intersect each other at least partially at a predetermined angle.

Specific examples are shown in this specification and dependent claims.

The proposed method is used specifically for cross-cutting, i.e., creating a streak structure on the surface of a gear in which a plurality of streaks intersect the corresponding streaks at a predetermined angle. Only a part of each of the first streaks may intersect each of the second streaks. However, preferably, all the first streaks intersect with at least one second streak.

In order to make a crosscut on the surface of the gear or on the gear wheel, according to the present invention, honing tools such as honing rings and honing wheels are oriented in the first direction along the gear using the first axis crossing angle. It is moved and the honing tool is moved along the gear in the second direction, opposite to the first direction, using a second axis crossing angle. Therefore, in the honing process provided by the present invention, the direction of movement of the honing tool along the gear is changed.

Further, according to the proposed method, the first axis crossing angle and the second shaft crossing angle are preferably made different. This means that the axis crossing angle changes when the moving direction of the honing tool changes. Therefore, for example, the streak structure can be applied from the lower left to the upper right while the honing tool is moving in the first direction, and the streak structure can be applied from the lower right to the upper left while the honing tool is moving in the second direction. The streaks applied during the movement in the first and second directions intersect and a crosscut is made, which is a section on the surface of each gear, especially on the sides of the teeth forming each gear. It is applied over the compartments, which is expected to effectively retain a film of lubricant such as oil, even when the gears are exposed to high loads, for example in a transmission.

In particular, the method of the present invention provides that a cross-cut structure is applied to the side surface of each tooth of the gear. To this end, according to a preferred embodiment of the proposed method, the gear is fixed to the honing machine, the honing ring of the honing machine is guided around the gear, and the honing ring is first along the gear. It moves in the direction of rotation and then in the second direction of rotation. In order to change the axis crossing angle of the gear with respect to the honing ring, the gear is reoriented with respect to the honing ring when the direction of movement of the honing ring is changed, that is, in a new direction.

In the present invention, the axis crossing angle is particularly defined as an axis passing through the center of the honing tool and orthogonal to the horizontal axis of the tool, for example, a rotation axis of the honing tool and an axis passing through the center of the gear and orthogonal to the horizontal axis of the gear, for example, a gear. It is considered to be the angle between the axis of rotation.

In the present invention, the streaks are considered to be fine irregularities generated on the surface of the gear, for example, which occurs in cross-cut grinding to a cylinder.

To move the honing tools provided by the present invention along their respective gears, the gears and / or honing tools are movable, especially during rotation.

The change in direction of movement made to form the surface structure according to the present invention should be such that the surface structure is applied on the gears by efficient kinematics, i.e. execution of a high speed movement sequence, which is a high load. It is also suitable for holding a film of lubricant on gears, for example when used in transmissions. Therefore, the method optimizes oil wetting on each of the teeth or sides of the gears, resulting in greater efficiency gains for related devices such as transmissions.

In an example of a possible embodiment of the method, it is assumed that gear honing is selected as the honing.

Gear honing, where gear teeth are honing, is different from, for example, cylindrical honing, where radial tools such as honing rings and honing wheels that move radially along the gear are usually used, which is the gear tooth. The teeth are processed by engaging in the gap.

In a further possible embodiment of the method, it is envisioned that an electric honing unit will be used to move the honing tool along the gears.

For example, an electric honing unit such as Gleason's 150SPH machine can be used to perform electric honing on gears. By adjusting the kinematics of the electric honing unit, it is possible to machine the gears according to this method. To this end, the electric honing unit can be configured to move the honing ring along the gear and / or along the honing ring, depending on the direction of movement of the gear or honing ring. The respective axis crossing angles between the honing ring and the gear are adjusted.

In a further possible embodiment of the method, it is assumed that the streaks are applied to the internal or external teeth of the gear.

The method makes it possible to apply surface structures to both internal and external gears to optimize the oil wettability of the gears. In particular, it is assumed that each tooth surface of the gear is machined to form a surface structure optimized for oil wetting, for example by cross-cutting. In this way, the crosscut forms a compartment that prevents the lubricant, such as oil, from slipping off the gear.

This method is particularly used in the manufacture of this gear.

Further advantages and embodiments will become apparent from this specification and the accompanying drawings.

It should be understood that the above features and the features described below can be used not only in specific combinations but also in other combinations or alone without departing from the scope of the present invention.

The present invention is schematically illustrated by embodiments in the drawings and will be described schematically and in detail with reference to the drawings.

The figure which shows the tooth of the gear which has the surface structure applied by the honing process by the prior art. FIG. 5 shows the teeth of a gear having a surface structure applied by honing according to a possible embodiment of the method.

FIG. 1 shows a gear tooth 1 machined using a honing ring by the prior art method. Here, the honing ring is moved in one direction along the tooth 1 while maintaining the axial crossing angle between the honing ring and the tooth 1. As a result, a surface structure having streaks 3 substantially parallel to each other is formed on the tooth 1 on the upper side 5 and the lower side 7 of the tooth 1. Here, the upper 5 streaks 3 approach the lower 7 streaks 3 without intersecting. This means that the streaks 3 form a flow path 9 through which a lubricant such as oil passes under the action of compressive forces, such as in use in a transmission, and outflow from the teeth 1 can occur. It is in a state and therefore the teeth are not well protected against pressure and temperature loads.

FIG. 2 shows gear teeth 20 machined by a honing ring according to a possible embodiment of the method. Here, the honing ring is moved in two directions along the tooth 20 at two different axial crossing angles. Therefore, the surface structure formed on the tooth 20 has lines 25 and 27 on both the upper 21 and the lower 23 of the tooth 20. The streaks 25 are applied during the forward movement of the honing ring, for example using a first axial crossing angle of 20 °. On the other hand, the streaks 27 are applied during the backward movement of the honing ring, that is, during the movement opposite to the forward movement of the honing ring, using, for example, an axial crossing angle of −20 °.

The gears move in opposite directions between the forward and backward movements of the honing ring.

It is noteworthy that the streaks 25 and the streaks 27 intersect each other to form a compartment 29, which is surrounded by the grooves 25 and 27, respectively. As a result, since the groove 25 and the groove 27 exhibit a barrier effect and hold the lubricant in the compartment 29, it is difficult for the lubricant such as oil introduced into the compartment 29 to escape from each compartment 29. is there. As a result, it is expected that the gear teeth 20 are protected by the lubricant even under a high load such as in a transmission. This in particular means that the gears can operate with low wear.

Claims (5)

A method of forming a surface structure on a gear in honing, where at least one honing tool is moved along the gear in a first direction using a first axis crossing angle, after which at least one honing tool is moved. Along the gear, using the second axis crossing angle, it was moved in a second direction opposite to the first direction, and at least one honing tool was moved in the first direction on the surface of the gear. Sometimes the first streak is at least a portion of each of the second streaks made when at least one honing tool is moved in a second direction on the surface of the gear at a predetermined angle. The first axis intersection angle and the second axis intersection angle are selected so as to intersect with each other .
The at least one honing tool is configured as a honing ring and is moved radially along the gears.
The first axis crossing angle and the second axis crossing angle, the axis of rotation of the honing tool, a method of an angle der characterized Rukoto between the rotating shaft of the gear. The method of claim 1, wherein gear honing is selected as the honing. The method of claim 1 or 2, wherein the electric honing unit is used when the honing tool is moved along the gears. The method according to any one of claims 1 to 3 , wherein the gear is cross-cut. The method according to any one of claims 1 to 4 , wherein the streaks are applied to the internal or external teeth of the gear.

Images